If your users have been completing submissions but the recipient(s) are not receiving the email from GoCanvas, the solution may be to Whitelist the GoCanvas email server IP.

Submission Emails Bouncing

Each email server is different so the recipient will need to look into the Whitelist setting for their specific email server. For example, if you need to whitelist an email server within Gmail, the administrator's account has advanced settings with a Spam, Phishing, and Malware tab where the Email Whitelist setting is located. 

• Email server IP to whitelist: 192.254.121.157
• Secondary IP: 149.72.212.167
• Ports used by GoCanvas: 25, 2525, 587, and 465 for mail (and 443 for web)